Synthesis of hydrophobic/alkoxylated polymers

ABSTRACT

The preparation of polymers which contain pendant hydrophobic groups or a mixture of both pendant hydrophobic and alkoxylated groups is accomplished by reacting a preexisting polymer having pendant acid amide and/or carboxylic groups with a primary or secondary amine in a substantially homogenous reaction mixture, the amine reactant including the desired hydrophobic and alkoxylated radicals. A unique polymer, having both pendant hydrophobic and alkoxylated groups, is provided.

This is a division of application Ser. No. 548,838, filed July 6, 1990.

TECHNICAL FIELD OF THE INVENTION

The present invention is in the technical field of polymer synthesis bypost-polymerization derivatization to provide polymers having pendantamide moieties that are substituted at the amide nitrogen withhydrophobic radicals and with a mixture of hydrophobic radicals andalkoxylated radicals, and polymers having unique combinations of suchgroups.

BACKGROUND OF THE INVENTION

Polymers prepared by the polymerization of relatively simple,ethylenically-unsaturated monomers such as (meth)acrylic acid and itsesters, (meth)acrylamide, maleic anhydride or maleic acid, crotonic acidand its esters, methyl vinyl ether, vinyl acetate, acrylonitrile,styrene and the like, are well known and are relatively easy to prepareby polymerization techniques well known in the art. The preparation ofpolymers that contain hydrophobic pendant groups by the polymerizationof ethylenically-unsaturated monomers which contain such hydrophobicgroups using conventional polymerization techniques is limited by theavailability of such monomers and possible complications arising in theattempt to incorporate such monomers into the polymer during thepolymerization. Complications during the polymerization may well occurif the hydrophobe-containing monomer does not have solubilitycharacteristics that are compatible with the desired polymerizationtechnique(s).

The difficulties generally encountered in the synthesis of polymerswhich contain pendant hydrophobic groups by conventional polymerizationtechniques for ethylenically-unsaturated monomers are generallymultiplied if the desired goal is to prepare a polymer which alsocontains pendant alkoxylated groups. The monomer availability problems,and complications in incorporating such diverse monomers into a polymer,are severely increased.

Post-polymerization derivatization of polymers prepared by conventionalpolymerization techniques, using relatively simple and readily availablemonomers, whereby pendant hydrophobic groups, or a mixture of pendanthydrophobic groups and pendant alkoxylated groups, are introduced intothe polymer avoids the difficulties regarding monomer availability andthe complications encountered in incorporating such unusual monomersduring a polymerization reaction. Such a post-polymerization process ishighly desirable if it is economically efficient. Economic efficiency isdependent upon many variables, including the efficiency with which theprocess proceeds, the reasonableness of the reaction conditionsrequired, the availability of both the basic polymer(s) to bederivatized and the derivatizing agent(s), the use of a minimum ofreaction steps, the ease at which the end product polymer can berecovered from the reaction mixture, and the like.

Polymers having unique mixtures of pendant hydrophobic groups andpendant alkoxylated groups are highly desirable given the uniqueproperties imparted to the polymer by the combinations of such diversegroups.

It is an object of the present invention to provide a process forpreparing a polymer containing pendant hydrophobic groups and bothpendant hydrophobic groups and pendant alkoxylated groups bypost-polymerization derivatization using polymers prepared byconventional techniques using readily available monomers. It is anobject of the present invention to provide such a process whereby suchgroups can be incorporated into a wide variety of pre-existingcommercially available polymers. It is an object of the presentinvention to provide such a process that minimizes the reaction stepsrequired and the time required for the derivatization. It is an objectto provide such a process that proceeds under relatively mild reactionconditions and minimizes any deletorious effects on the polymerstructure. It is an object of the present invention to provide such aprocess that generally can employ commercially available derivatizingagents. It is an object to provide such a process that employs generallya reasonably high concentration of reactants, and hence renders themethod economically desirable as to the end product yield for the giventime, equipment, energy and the like utilized. It is an object toprovide such a process wherein the polymer end product is easilyrecovered from the reaction mixture.

It is an object of the present invention to provide a unique polymerhaving incorporated thereinto mixtures of hydrophobic and alkoxylatedpendant groups.

These and other objects of the present invention are described in moredetail below.

DISCLOSURE OF THE INVENTION

The present invention provides a method of preparing polymers havingpendant hydrophobic groups or mixtures of both pendant hydrophobicgroups and pendant alkoxylated groups by derivatization of pre-existingpolymers in a substantially homogeneous reaction mixture. Thederivatization process employs pre-existing polymers that containpendant groups having the structure of Formula I: ##STR1## wherein n iszero or an integer from 1 to about 10, and X is --NH₂, --OH, or --O⁻,and salts thereof, and mixtures or combinations of such pendant groups.

By "salts" is meant herein alkali metal salts, alkaline earth metalsalts, ammonium salts, amine salts, alkanol amine salts, and the like.

The derivatization process employs as the source of hydrophobicradicals, or hydrophobic and alkoxylated radicals, primary and secondaryamines containing the desired radical(s).

The reaction mixture is comprised of the reactants, i.e., the polymer(s)and the amine(s), and a reaction medium in which the reactants aresoluble or substantially homogenously dispersible. In a preferredembodiment an aqueous reaction medium is employed.

When the polymers employed are derived from ethylenically unsaturatedmonomer, the pendant groups subject to derivatization are contained in apolymer "unit" or "mer unit" (a segment of the polymer having twoadjacent backbone carbons) having the structure of Formula II: ##STR2##wherein R₁, R₂ and R₃ are independently hydrogen or substituent otherthan hydrogen and wherein Y is the pendant group(s) the structure ofwhich is defined above by Formula I.

By "substituent" is meant herein a single or multivalent radical otherthan hydrogen covalently bonded to a carbon or nitrogen of thereferenced molecule.

When R₁, R₂ and/or R₃ of Formula II above are substituents other thanhydrogen, typically they are C₁₋₄ alkyl or carboxylic substituents.

The derivatization process is a (trans)amidation reaction whereby thehydrophobic radicals or hydrophobic and alkoxylated radicals of the endproduct polymer are substituents to the nitrogen of an acid amide group,as discussed in more detail below.

The present invention also provides unique polymers that contain bothhydrophobic and alkoxylated pendant groups which are substituents to thenitrogen of an acid amide group, as discussed in more detail below.

PREFERRED EMBODIMENTS OF THE INVENTION

The polymers employed in the derivatization process contain pendantgroups having the structure of Formula I above and include pendantgroups having carboxyl, carboxylate, and acid amide moieties. Suchmoieties are the reactive groups that enter the (trans)amidationreaction with the amine derivatizing agents. There is no theoreticalminimum of mer units containing such groups required of the polymeremployed and the derivatization theoretically can be accomplished withas little as one such mer unit per polymer molecule. Nonetheless it isbelieved that to achieve a favorable reaction without employing anysignificant excess of derivatizing agent, and to provide an end productpolymer having a reasonable degree of properties derived by virtue ofthe derivatization, the starting material polymer should have 10 molepercent or more of mer units containing the pendant groups having thestructure of Formula I above.

Ethylenically-unsaturated monomers that provide to a polymers pendantgroups having the structure of Formula I include (meth)acrylamide,(meth)acrylic acid and salts thereof, crotonic acid, maleic acid, maleicanhydride, and the like and other monomers, for instance acrylonitrile,(meth)acrylic acid esters, and the like, that may be converted into merunits having the desired pendant groups after incorporation into apolymer, for instance by hydrolysis. The monomers enumerated herein areof course not the only monomers that provide the desired polymer pendantgroups but instead are representative of monomers that are both readilycommercially available and are polymerizable by very simple and wellknown polymerization techniques, and hence the employment of polymersprepared from such monomers is a preferred embodiment of the invention.

Polymers that may be employed in the derivatization process may containany amount of mer units other than those providing pendant groups ofFormula I above, provided that such other mer units do not comprise theentirety of the polymer. As mentioned above, however, it is believedthat to achieve a favorable reaction without employing any significantexess of derivatizing agent, and to provide an end product polymerhaving a reasonable degree of properties derived by virtue of thederivatization, the amount of mer units not providing pendant groups ofthe Formula I above should not exceed about 90 mole percent.

Generally any monomer that is polymerizable with the monomers providingpendant groups of the Formula I above may be incorporated into thepolymer, although considerations such as ease of polymerization of thegiven monomer mixture, and the propensity of the comonomers to engage inside reactions or interfere with the derivatization reaction, may befactors in the selection of comonomers. For instance, under typical freeradical initiated polymerization conditions, vinyl acetate is generallyconsidered a good comonomer with maleic anhydride but not with acrylicacid, and hence its desirability as a comonomer is dependent upon thetype of monomer that will be providing the necessary pendant groups.Other good comonomers with maleic anhydride are methyl vinyl ether,styrene or the like. Good comonomers with acrylic acid and acrylamideinclude the alkyl esters of acrylic acid, acrylonitrile and the like.Other possible considerations concerning the selection of suitablecomonomers are the properties of the starting material polymer and theend material polymer. For instance, a hydrophilic comonomer may bepreferred when it is desired to increase the water solubility of thestarting material polymer and/or the end material polymer, or ahydrophobic comonomer may be selected to decrease water solubility whendesired. An amount of butyl acrylate may be used as a comonomer toprovide a degree of tack to the end product polymer. One comonomer maybe more advantageous than another if the monomer itself is less toxicand the toxicity of residual monomer in the end product polymer is aconsideration for the intended use of the polymer. The starting materialpolymer may be a random polymer, or other than a random polymer.

The derivatizing agents are primary and/or secondary amines having ahydrophobe radical, or mixtures of such amines with primary and/orsecondary amines having alkoxylated radicals. For instance, the methylradical of methyl amine is a hydrophobic radical, particularlyconsidering the diminished hydrophilicity when a pendant acid amidegroup (--CONH₂) is derivatized to an N-substituted methyl amide group(CONHCH₃). Hydrocarbon radicals having three or more carbon atoms aresignificantly hydrophobic for purposes of the present invention, andhydrophobic radical having 12 or more carbon atoms are for some purposesof the present invention preferred. The hydrophobic radical need not besaturated, and for some purposes of the present invention a degree ofcarbon-to-carbon unsaturation is preferred for long-chain hydrophobicradicals. The hydrophobic radical may contain other substituentsprovided that such substituents do not destroy the hydrophobic nature ofthe radical. While primary amines are preferred, the use of secondaryamines is not hereby excluded.

The employment of a mixture of both amines having hydrophobic radicalsand amine having alkoxylated radicals provides unique end productpolymers having significant diverse pendant groups. Alkoxylated radicalsgenerally contain ethoxy (--CH₂ CH₂ O--) groups or propoxy (--CHCH₃ CH₂O--) groups, generally derived from ethylene oxide and propylene oxide,or mixtures of both types of alkoxy groups. The alkoxylated aminederivatizing agent should contain an amino group, preferably a primaryamino group, and at least one alkoxy group, and may contain othergroups, for instance hydrocarbon groups. A very useful group ofcommercially available alkoxylated primary amines are sold by the TexacoChemical Company under the tradename of "Jeffamine". (Jeffamine is atrademark of the Texaco Chemical Company, a Division of Texaco Inc.) Forinstance, Jeffamine M-600 has the following structure: ##STR3## As seenfrom the structural formula above, Jeffamine M-600 contains both ethoxyand propoxy groups and is reported to have more than 1.71 meq/g ofprimary amine. Another Jeffamine product having a mixture of ethoxy andpropoxy groups is Jeffamine M-1000 which has the following structure:##STR4## As seen from the use of fractional subscripts in the structuralformula above, Jeffamine M-1000 is a mixture of linear polyether aminesvarying somewhat in their total ethoxy and propoxy groups. JeffamineM-1000 is reported to have a total amine content of 0.85 meq/g and aprimary amine content of 0.83 meq/g. Jeffamine M-300 and Jeffamine M-360both contain a reasonably significant hydrocarbon group. Jeffamine M-300has the structure of: ##STR5## wherein R₄ is a mixture of linear C₁₀ toC₁₂ alkyl groups and x has an average value of 1. Jeffamine M-360 hasthe structure of: ##STR6## and has a total amine content of greater than2.47 meq/g and a primary amine content of greater than 2.39 meq/g.

Another useful groups of commercially available alkoxylated primaryamines are sold by the Texaco Chemical Company under the tradename of"Surfonamine MNPA" (Surfonamine is a trademark of the Texaco ChemicalCompany), and this series of alkoxylated amines has the generalstructural formula of: ##STR7## wherein m, the number of ethoxy radicalsper molecule, varies from about 1 to about 12, and n, the number ofpropoxy radicals per molecule, varies from about 1 to about 4, for thevarious amines of the series, i.e., Surfonamine MNPA-380, 510, 750, and860. These nonylphenol alkoxylated primary amines contain both ahydrocarbon chain and an aromatic radical, in addition to the alkoxy andamine radicals.

By alkoxylated amine is meant herein generally an amine, either primaryor secondary, having at least on alkoxy radical, either ethoxy orpropoxy, within its chemical structure. In preferred embodiment, thealkoxylated amine is an amine wherein the alkoxy radical(s) comprise atleast one percent of the amine's formula weight. In more preferredembodiment, the alkoxylated amine is an amine wherein the alkoxyradical(s) comprise at least five percent of the amine's formula weight,and in even more preferred embodiment, at least ten percent of theamine's formula weight.

A useful group of hydrophobic radical containing amines are thealiphatic amines commercial available under the tradename of "Armeen"from Armak Chemicals ("Armeen" is a registered trademark of Akzo ChemieAmerica for the aliphatic amines produced by Armak Chemicals). Among theavailable Armeen primary amines are soyaamine 5NH₂) sold under thetradenames of Armeen S and Armeen SD. Armeen SD has a water solubility(in percent of solution weight) of about 10.13 at 50° C. and 4.01 at 80°C. It has a primary amine content of 98% and a secondary amine contentof 2% (ASA). At 25° C. it is a paste, and at 55° C. it has a viscosityof about 38.5 SSU. Although it is considered an octadecenyl amine asnoted by the formula above, the reported carbon chain distribution is70% octadecenyl, 14% octadecyl, 5% octadecadienyl, 4% for each ofhexadecyl and octadecenyl, and more minor amounts of other carbonchains. Armeen S is a less expensive, undistilled form of suchsoyaamine. Among other Armeen primary amines are Armeen HTD, ahydrogenated tallow amine (C₁₈ H₃₇ NH₂) having a water solubility of4.39 at 80° C. (a nonfluid mixture in water at 60° C.), Armeen 16D, ahexadecylamine (C₁₆ H₃₃ NH₂) which has a water solubility of 12.99 at60° C. and 5.47 at 80° C., and Armeen 12D, a dodecylamine (C₁₂ H₂₅ NH₂),which is a liquid at 25° C., and has a water solubility of 24.35 at 50°C. and 12.50 at 80° C. Among Armeen secondary amines are Armeen 2C, adicocoamine, (C₁₂ H₂₅)₂ NH, a solid at 25° C.,and Armeen 2HT, adi(hydrogenated-tallow)amine, (C₁₈ H₃₇)₂ NH₂, which is also solid at 25°C.

In preferred embodiment the (trans)amidation process is conducted in anaqueous medium. The use of an aqueous medium is generally less expensivethan a nonaqueous medium. The end product polymer is easier to isolatefrom an aqueous medium. An aqueous medium moreover minimizes thetoxicity of the reaction mixture, and the toxicity of the end productpolymer if not completely isolated from the reaction medium. Inaddition, for some use applications, if an aqueous reaction medium isemployed, the end product polymer isolation step may not be required.While all of such advantages ensue from the use of an aqueous reactionmedium, the employment of an aqueous reaction medium heretofore wouldgenerally be considered contrary to the objectives of obtaining areasonable degree of derivatization and an economically efficientprocess. In an aqueous reaction medium, interference with thederivatization would be expected due to the propensity of such system tolead to an excessive degree of hydrolysis of the reactants. In addition,it is surprising, given the water solubilities of the present reactants,that an efficient derivatization reaction proceeds in an aqueous mediumat relatively high concentrations of reactants, and concommitantly in asystem having relatively low fluidity.

The present invention does not, in its broadest definition, exclude theuse of nonaqueous reaction mediums, for instance dimethyl sulfoxide("DMS") or various other organic liquids.

The reactants should be soluble or substantially homogeneouslydispersible in the reaction medium employed, given the concentrations ofreactants used. Hydrophobe-containing amine reactants having some degreeof carbon-to-carbon unsaturation within the hydrophobic moiety aregenerally more fluid than the equivalent fully saturated amines and suchfluidity facilitates dispersing such reactants in the reaction medium,particularly when the medium is water. When polymer reactants of verylimited water solubility are employed in an aqueous reaction medium, theconcentration of the reactants in such process can of course be loweredif needed for to disperse the reactants. The water solubility or waterdispersibility characteristics of the starting material polymer aredependent upon the balance between its hydrophobic and hydrophilicpendant groups, and its molecular weight, and thus while in someinstances one can select the starting material polymer so as to providethe desired degree of water solubility, in other instances thepreference for a given polymer is an overriding factor.

As long as a reasonable degree of substantially homogeneous dispersionof the reactants in the reaction medium is achieved, the startingreaction mixture need not even be fluid at room temperature.

The end product polymer, even when an aqueous reaction medium isemployed may possibly not be water soluble or water dispersible.

The (trans)amidation reaction is conducted at elevated temperatures andunder pressures that exceed atmospheric pressure. The reaction generallyis accomplished in a closed vessel at a temperature of from about 120°C. to about 200° C.

The starting material polymer may contain participating pendant groupsthat are wholly acid amide groups, for instance the pendant groups of(meth)acrylamide mer units, or that are wholly carboxylic groups, forinstance the pendant groups of (meth)acrylic acid or maleic anhydridemer units. If the former situation existed, the process would beconsidered a transamidation reaction whereby acid amide groups arederivatized by amine reactants to N-substituted acid amide groups. Ifthe latter situation existed, the process would be considered anamidation reaction whereby carboxylic groups would be derivatized byamine reactants to N-substituted acid amide groups. Hence the process isdeemed a (trans)amidation reaction, and it has been found that thederivatization proceeds extremely efficiently when the starting materialpolymer contains a mixture of both carboxylic groups and acid amidegroups.

The derivatization reaction generally does not proceed to the exhaustionof all of the derivatizing amine employed, and hence it is desirable touse a greater charge of amine reactant than stoichiometrically requiredfor the desired degree of derivatization.

A one to one mole ratio of participating polymer pendant groups toderivatizing amine possibly may be used, and in fact less participatingpendant groups and amine reactant, on a mole basis, may be reasonablyused. Generally, however, it is desirable to have potentialparticipating pendant groups in excess of the amount required for theextent of derivatization desired, particularly when such potentiallyparticipating pendant groups themselves impart desired characteristicsto the end product polymer.

The derivatization reaction should be permitted to proceed for at leasta one-half hour duration, and preferably for a time period of from aboutthree to about eight hours.

In Examples 1 through 8 that follow, the derivatization process wasconducted using a concentration of starting material polymer of fromabout 20 to about 32 weight percent based on the entire reaction mixture(polymer, derivatizing agent and water medium). In highly preferredembodiment the concentration of starting material polymer on such basisis at least 20 weight percent, although a reasonably efficient processensues when the concentration of the starting material polymer is as lowas 10 weight percent, same basis. As discussed above, at times it may benecessary to decrease the concentration of starting material polymer soas to use a desired polymer, and then the polymer concentration may fallto as low as 5 weight percent or less.

The concentration of the end material polymer in the reaction mixture isof course dependent on the amount of derivatizing agent employed and thedegree of reaction, in addition to the initial polymer concentration. InExample 3 that follows, the starting material polymer's concentrationwas about 31 weight percent, and the end material polymer'sconcentration was about 43 weight percent.

As discussed above, the starting material polymer must contain pendantgroups having the structure of Formula I above. Such pendant groupscontain either a carboxylic radical (wherein X of Formula I is --OHand/or --O⁻) or an acid amide radical (wherein X of Formula I is --NH₂).In preferred embodiment the mole ratio of carboxylic radical containingpendant groups to acid amide containing pendant groups in the startingmaterial polymer ranges from about 1:0 to about 1:9, and in morepreferred embodiment ranges from about 1:0 to about 1:3.

The unique polymers of the present invention contain both hydrophobicand alkoxylated groups which are substituents to the nitrogen of pendantacid amide groups. The presence of these diverse groups within the samepolymer provides unique characteristics for various end useapplications. For instance, when used in water systems, both types ofpendant groups may have a propensity to attach to substrates. Thehydrophobic moieties will tend to attach to substrates by virtue oftheir hydrophobic nature, while the alkoxylated moieties may may tend toattach to substrate surfaces due to hydrogen bonding and likemechanisms. The presence of both types of side chains provides uniquethickening characteristics. It is believed that to provide uniquecharacteristics in applications where substrate attachment is desired,for instance soil release or shale stabilization applications, or inapplications where unique thickening properties are desired, the polymermay contain as little as 0.1 mole percent of each type of group, basedon total moles of mer units in the polymer. In preferred embodiment, thepolymer contains at least 1 mole percent of each type of group(hydrophobic moiety and alkoxylated moiety), based on total moles of merunits in the polymer. In more preferred embodiment, the polymer containsat least 2.5 mole percent of each type of group, same basis.

When an aqueous reaction medium is employed, a high efficiency processrequires the molecular weight of the starting material polymer to belimited to about no more than 200,000, and in some instances, forinstance if a homopolymer of acrylamide is used, to no more than 100,000(weight average molecular weight). In preferred embodiment the startingmaterial polymer is of rather low molecular weight, for instance no morethan 50,000, and more preferably no more than about 25,000, and thepreference for such low molecular weight starting material polymers isparticularly germaine to the unique polymers having both hydrophobic andalkoxylated groups from which unique end use characteristics flow.

Preferably the molecular weight of the starting material polymer is atleast about 2,000 (weight average molecular weight).

In general, regardless of whether the derivatizing agent is ahydrophobe-containing amine or a mixture of hydrophobe-containing amineand alkoxylated amine, the degree of derivatization desired is toincorporate at least 0.1 mole percent of derivatized groups into thepolymer, based on total moles of mer units in the polymer, and morepreferably to incorporate at least mole percent of the derivatizedgroups into the polymer, same basis.

In preferred embodiment, the mole ratio of reactants, i.e., pendantpolymer groups having the structure of Formula I above (participatingpendant groups) to the amine-containing derivatizing agent(s) is fromabout 1 to about 1:2, and in more preferred embodiment is from about50:1 to about 1:1.

EXAMPLE 1

An acrylamide homopolymer having a weight average molecular weight ofabout 7,500 was derivatized by transamidation reaction with soya-amineas follows. To 195 grams of a 33 weight percent aqueous solution of thepolyacrylamide was added 25.11 grams of Armeen S, which is describedabove. This amount of Armeen S was a 10 mole percent charge based on thetotal number of mer units in the polymer charge. This admixture wasplaced into a 300 ml. Parr reactor. The reactor was purged withnitrogen; then sealed, heated internally to 150° C., and held at thattemperature for a 5 hour reaction period. The reaction mixture recoveredfrom the cooled reactor was a white milky liquid. Based on L.C. analysisfor residual amine, the soya-amine was determined to have reacted to theextent of 90 weight percent of its initial charge.

EXAMPLE 2

Example 1 was repeated except the amount of the polyacrylamide solutionwas decreased to 175 grams and the mole percent charge of the soya-aminewas increased to 20 mole percent (45.06 grams of Armeen S). The reactionmixture recovered was again a white milky liquid and, based on L.C.analysis for residual amine, the soya-amine was determined to havereacted to the extent of 68 weight percent of its initial charge.

EXAMPLE 3

An acrylic acid/acrylamide copolymer having a weight average molecularweight of about 16,000 was derivatized by reaction with soya-amine asfollows. To 185 grams of a 35 weight percent aqueous solution of thecopolymer was added 25.09 grams of Armeen S. This admixture was placedinto a 300 ml. Parr reactor. The reactor was purged with nitrogen, thensealed, heated internally to 150° C., and held at that temper-ature fora 5 hour reaction period. The reaction mixture recovered from the cooledreactor was waxy solid. Based on L.C. analysis for residual amine, thesoya-amine was determined to have reacted to the extent of 100 weightpercent of its initial charge.

EXAMPLE 4

Example 3 was repeated except the amount of the copolymer solution wasdecreased to 170 grams and the charge of the soya-amine was increased to46.10 grams. The reaction mixture recovered was again a waxy solid and,based on L.C. analysis for residual amine, the soya-amine was determinedto have reacted to the extent of 97 weight percent of its initialcharge.

EXAMPLE 5

An acrylic acid/acrylamide copolymer having a weight average molecularweight of about 16,000 was derivatized by reaction with both soya-amineand an alkoxylated amine (primary amine) in a single reaction asfollows. To 165grams of a 35 weight percent aqueous solution of thecopolymer was added 11.9 grams of the soya-amine (Armeen S) and 40.38grams of the alkoxylated amine (Jeffamine M-1000 which is describedabove). This admixture was placed into a 300 ml. Parr reactor. Thereactor was purged with nitrogen, then sealed, heated internally to 150°C., and held at that temperature for a 5 hour reaction period. Thereaction mixture recovered from the cooled reactor had a paste-likeconsistency. Based on L.C. analysis for residual amine, the soya-aminewas determined to have reacted to the extent of 95 weight percent of itsinitial charge, and the alkoxylated amine was determined to have reactedto the extent of 83 weight percent of its initial charge.

EXAMPLE 6

Example 5 was repeated except the amount of the copolymer solution wasdecreased to 135 grams, the charge of the soya-amine was increased to18.31 grams, and the charge of the alkoxylated amine was increased to66.08 grams. The reaction mixture recovered was again of paste-likeconsistency. Based on L.C. analysis for residual amine, the soya-aminewas determined to have reacted to the extent of 86 weight percent of itsinitial charge and the alkoxylated amine was determined to have reactedto the extent of 58 weight percent of its initial charge.

EXAMPLE 7

An acrylamide homopolymer having a weight average molecular weight ofabout 7,500 was derivatized as follows. To 170 grams of a 33 weightpercent aqueous solution of the polyacrylamide was added 39.51 grams ofJeffamine M-1000 and 10.94 grams of Armeen S, both of which aredescribed above. These amounts were a 5 mole percent charge of both theJeffamine M-1000 and Armeen S based on the total number of mer units inthe polymer charge. This admixture was placed into a 300 ml. Parrreactor. The reactor was purged with nitrogen, then sealed, heatedinternally to 150° C., and held at that temperature for a 5 hourreaction period. The reaction mixture recovered from the cooled reactorwas a brown liquid. Based on L.C. analysis for residual amine, thesoya-amine (Armeen S) was determined to have reacted to the extent of 38weight percent of its initial charge, and the alkoxylated amine wasdetermined to have reacted to zero weight percent of its initial charge.

EXAMPLE 8

Example 7 was repeated except the amount of the polyacrylamide solutionwas decreased to 135 grams, and the mole percent charges of both thesoya-amine and alkoxylated amine were increased to 10 mole percent(62.75 grams of Jeffamine M-1000 and 17.38 grams of Armeen S). Thereaction mixture recovered again was a brown liquid, and based on L.C.analysis for residual amine, the soya-amine was determined to havereacted to the extent of 34 weight percent of its initial charge and thealkoxylated amine was determined to have reacted to the extent of zeroweight percent of its initial charge.

EXAMPLE 9

The product polymers of Examples 1 through 8 were analyzed for molepercent of carboxylate mer units by titration at pH of 10. The resultsof such carboxylate determinations are set forth below in Table I.

                  TABLE I                                                         ______________________________________                                        Example No. of Polymer                                                                       Mole Percent of Carboxylate-                                   Preparation    Containing Mer Units                                           ______________________________________                                        1              42                                                             2              32                                                             3              50                                                             4              47                                                             5              53                                                             6              42                                                             7              41                                                             8              34                                                             ______________________________________                                    

INDUSTRIAL APPLICABILITY OF THE INVENTION

The present invention is applicable to the industries requiring agentsfor thickening, soil release and the like, wherein the polymers havingpendant hydrophobic groups or pendant hydrophobic and alkoxylated groupsare useful.

I claim:
 1. A polymer having pendant groups of the structural formulas##STR8## wherein n is zero or an integer of from 1 to about 10, R' is ahydrophobic radical, R" is an alkoxylated radical, and R₂ is hydrogen ora substituent other than hydrogen.
 2. The polymer of claim 1 whereinsaid hydrophobic radical contains at least three carbon atoms.
 3. Thepolymer of claim 2 wherein said hydrophobic radical contains at leasttwelve carbon atoms.
 4. The polymer of claim 1 wherein the alkoxyradicals within the alkoxylated radical comprise at least five percentof the alkoxylated radical's formula weight.
 5. The polymer of claim 1wherein said polymer contains at least 1 mole percent of mer unitshaving said pendant groups containing a hydrophobic radical, and atleast 1 mole percent of mer units having said pendant groups containingan alkoxylated radical.
 6. The polymer of claim 5 wherein said polymercontains at least 2.5 mole percent of mer units having said pendantgroups containing a hydrophobic radical, and at least 2.5 mole percentof mer units having said pendant groups containing an alkoxylatedradical.
 7. The polymer of claim 1 wherein the molecular weight of saidpolymer excluding said hydrophobic and alkoxylated radicals is up to50,000.
 8. The polymer of claim 1 wherein the molecular weight of saidpolymer excluding said hydrophobic and alkoxylated radicals is up to25,000.